Inflammatory bowel disease (IBD), which occurs world-wide and afflicts millions of people, is the collective term used to describe three gastrointestinal disorders of unknown etiology: Crohn's disease (CD), ulcerative colitis (UC), and indeterminate colitis (IC). IBD, together with irritable bowel syndrome (IBS), will affect one-half of all Americans during their lifetime, at a cost of greater than $2.6 billion dollars for IBD and greater than $8 billion dollars for IBS. A primary determinant of these high medical costs is the difficulty of diagnosing digestive diseases and how these diseases will progress. The cost of IBD and IBS is compounded by lost productivity, with people suffering from these disorders missing at least 8 more days of work annually than the national average.
Despite the successes of anti-TNFα therapies in the treatment of IBD, a subpopulation of patients are refractory to treatment, highlighting an unmet medical need for new therapies. Vedolizumab is a gut-specific, α4β7 integrin-neutralizing monoclonal Ab, which does not affect peripheral blood cell counts and appears to lack systemic effects. Vedolizumab is a new anti-inflammatory treatment option for the management of therapy-refractory patients.
There is a need in the art for methods of therapeutic management of diseases such as ulcerative colitis and Crohn's Disease using an individualized approach to monitor drug efficacy and optimize therapy accordingly. The methods need to include assessing disease course and clinical parameters such as pharmacodynamics, disease activity indices, disease burden, and inflammatory biomarkers. There is a need to predict whether a patient will respond to vedolizumab therapy. The present invention satisfies this and other needs.